U.S. President Barack Obama, right, speaks as Park Geun Hye, president of South Korea, listens during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, speaks as Park Geun Hye, president of South Korea, listens during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, listens as Park Geun Hye, president of South Korea, speaks during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, listens as Park Geun Hye, president of South Korea, speaks during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, listens as Park Geun Hye, president of South Korea, speaks during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, listens as Park Geun Hye, president of South Korea, speaks during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, left, exits with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, left, exits with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, left, exits with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, left, exits with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, exits with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, exits with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, shakes hands with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, shakes hands with Park Geun Hye, president of South Korea, after a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

Park Geun Hye, president of South Korea, speaks during a press conference with U.S. President Barack Obama, unseen, in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

Park Geun Hye, president of South Korea, speaks during a press conference with U.S. President Barack Obama, unseen, in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, listens as Park Geun Hye, president of South Korea, speaks during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images

U.S. President Barack Obama, right, listens as Park Geun Hye, president of South Korea, speaks during a press conference in the East Room of the White House in Washington, D.C., U.S., on Tuesday, May 7, 2013. Obama and Park are seeking to demonstrate a solid front in the face of threats from North Korea and broader tensions in the region. Photographer: Pete Marovich/Bloomberg via Getty Images